Heater fan fault in K12
- Thread starter t8769
- Start date
Can anyone suggest a way to fix this, it keeps cutting out.
When I pull on the power wire it works again, then goes a day later.
There's no connection, the wire goes directly into the fan.
So I guess a repair will involve pulling the thing out, which is a lot of work.
Has anyone dealt with this, any ideas on how to fix it, or the best way to do it?
If anyone has the manual to do this, I'd appreciate if you could let me have this - do we need to pull out the dash?
Thanks
When I pull on the power wire it works again, then goes a day later.
There's no connection, the wire goes directly into the fan.
So I guess a repair will involve pulling the thing out, which is a lot of work.
Has anyone dealt with this, any ideas on how to fix it, or the best way to do it?
If anyone has the manual to do this, I'd appreciate if you could let me have this - do we need to pull out the dash?
Thanks
Yes indeed,be prepared for a fairly big job ,steering wheel and airbag module also has to come out,but if you take your time and are patient with the clips etc.you should get through it..I would think a day and a half to get everything out and back in if you are an amateur mechanic like me. I would clean up the connector going into the motor too,or did you say you didn't have one .There is a detailed procedure in the workshop manual I found on this site,which I followed...just can't find it now but let me know if you want it as I think I stored it on another laptop.There is another thread whereby another member took out windscreen or at least it was being replaced so did this job at the same time..
You may find the following threads helpful in resolving the K12 heater fan nightmare in a rational sequence with minimum dismantling? Take your choice.
https://www.micra.org.uk/threads/k12-blower-fan-removal.65452/#post-732263
https://www.micra.org.uk/threads/k12-rh-drive-heater-motor-removal-replacement.42571/
Used Haynes workshop manuals available from a tenner or less on EBay /Amazon
Good luck
Problem with heater fan suddenly not working can be due to bad electrical contacts at Fan Resistor. This is located behind glove compartment and electrical connector to it has four wires. To separate the two halves of the connector press the white centre clip and prise apart with a screwdriver. Try bending the four tabs, very slightly on the female side of the connector to ensure better contact and re-assemble, making sure to press two halves tightly together. This solved my problem on two occasions without buying a new Resistor,which is expensive.
Biggest part of job is removing the glove compartment to get at the Resistor. First, prise out the two plastric hinge pins under the compartment door flap and then remove the six fixing screws to take out the complete compartment.
I'm resurrecting this thread as my blower stopped working completely a couple of months ago and with the arrival of the cold wet weather I thought that I should get my arse in gear and fix it. 
Well as anyone familiar with this problem on the RH drive K12 will know, that to replace the blower motor is a mega difficult job entailing stripping out the whole dash and/or removing the steering column and pedal assembly.
This common 'motor failure' (which it actually isn't) is due to the poor design of the plug/socket arrangement on the blower assembly.
I realised that I could get at the plug/socket by removing the top cover of the dash (first the good news), however you can only really see it from the outside of the car, through the windscreen!.
Having studied it that way I realised that the connector had a clip at the end closest to the passenger compartment and a horizontal peg closest to the engine.
When you release the clip, you can rotate the connector up till the 'business end is clear of the hole in the blower assembly, then slide it to the right (towards the steering wheel). off of the peg, and lift it up into clear sight, attached to the loom.
On inspection it was seen that there was signs of arcing on the exposed connector at the clip end.
looking into the exposed hole in the top of the blower assembly (through the windscreen with a torch) it could be seen that there were two male spade connectors sticking up which the contacts on the plug were 'supposed to mate with' when it was clipped into place, but in practice fail miserably to make a good reliable long term connection. The spade connector at the front, pivot end, (which is the +ve one) is a 3/16" or 4.8mm spade and the rear one (-ve, which goes back to the resistor block) is a 1/4" or 6.3 mm one.
The obvious answer was to make up two wire 'tails' with the appropriate female spade connectors crimped on, put them on the exposed male spades and splice the wires into the feed cables before the plug. Sounds easy doesn't it?
Trouble is that you have to do this from inside the car with no way of seeing what you are doing..
Well I solved the problem by taping a small screw driver vertically to the female connector and wire a with my trusty assistant (our combined ages are 143!) standing on a stool, peering through the windscreen with a torch saying 'left a bit, right a bit, back a bit, now push down', we had both wires firmly connected in about ten minutes.
The next stage was to expose a short area of both feed wires on the loom, behind the crappy plug, connect the appropriate tail from the motor to them, solder in place and liberally cover both connections with insulation tape.
I also wrapped the 'business end' of the redundant plug with several layers of pvc tape to prevent any possible shorting out behind the dash.
It was fairly easy then to tuck the old plug behind the main loom and secure it with a cable tie to prevent rattles.
At this point it seemed a good idea to actually test that the fix had work and lo and behold we have a working blower again that functions on all settings.
This still left the exposed elongated oval hole in the top of the blower assembly that had the two new wire coming out of it., anything dropping in there would be likely to cause a short circuit and smoke!
I solved this by taking a large piece of BluTack (about 65mm by 25mm) and moulded it over the hole and around the wires, job done!
All that was left to do was to reinstate the dash top panel and put all of the tools away.
It ain't easy but it can be done with minimal cost.
Well as anyone familiar with this problem on the RH drive K12 will know, that to replace the blower motor is a mega difficult job entailing stripping out the whole dash and/or removing the steering column and pedal assembly
.This common 'motor failure' (which it actually isn't) is due to the poor design of the plug/socket arrangement on the blower assembly
.I realised that I could get at the plug/socket by removing the top cover of the dash (first the good news), however you can only really see it from the outside of the car, through the windscreen!
.Having studied it that way I realised that the connector had a clip at the end closest to the passenger compartment and a horizontal peg closest to the engine.
When you release the clip, you can rotate the connector up till the 'business end is clear of the hole in the blower assembly, then slide it to the right (towards the steering wheel). off of the peg, and lift it up into clear sight, attached to the loom.
On inspection it was seen that there was signs of arcing on the exposed connector at the clip end.
looking into the exposed hole in the top of the blower assembly (through the windscreen with a torch) it could be seen that there were two male spade connectors sticking up which the contacts on the plug were 'supposed to mate with' when it was clipped into place, but in practice fail miserably to make a good reliable long term connection. The spade connector at the front, pivot end, (which is the +ve one) is a 3/16" or 4.8mm spade and the rear one (-ve, which goes back to the resistor block) is a 1/4" or 6.3 mm one.
The obvious answer was to make up two wire 'tails' with the appropriate female spade connectors crimped on, put them on the exposed male spades and splice the wires into the feed cables before the plug. Sounds easy doesn't it?
Trouble is that you have to do this from inside the car with no way of seeing what you are doing.
.Well I solved the problem by taping a small screw driver vertically to the female connector and wire a with my trusty assistant (our combined ages are 143!) standing on a stool, peering through the windscreen with a torch saying 'left a bit, right a bit, back a bit, now push down', we had both wires firmly connected in about ten minutes
.The next stage was to expose a short area of both feed wires on the loom, behind the crappy plug, connect the appropriate tail from the motor to them, solder in place and liberally cover both connections with insulation tape.
I also wrapped the 'business end' of the redundant plug with several layers of pvc tape to prevent any possible shorting out behind the dash.
It was fairly easy then to tuck the old plug behind the main loom and secure it with a cable tie to prevent rattles.
At this point it seemed a good idea to actually test that the fix had work and lo and behold we have a working blower again that functions on all settings.
This still left the exposed elongated oval hole in the top of the blower assembly that had the two new wire coming out of it., anything dropping in there would be likely to cause a short circuit and smoke!
I solved this by taking a large piece of BluTack (about 65mm by 25mm) and moulded it over the hole and around the wires, job done!
All that was left to do was to reinstate the dash top panel and put all of the tools away.
It ain't easy but it can be done with minimal cost.
I'm resurrecting this thread as my blower stopped working completely a couple of months ago and with the arrival of the cold wet weather I thought that I should get my arse in gear and fix it.
Well as anyone familiar with this problem on the RH drive K12 will know, that to replace the blower motor is a mega difficult job entailing stripping out the whole dash and/or removing the steering column and pedal assembly
This common 'motor failure' (which it actually isn't) is due to the poor design of the plug/socket arrangement on the blower assembly
I realised that I could get at the plug/socket by removing the top cover of the dash (first the good news), however you can only really see it from the outside of the car, through the windscreen!
Having studied it that way I realised that the connector had a clip at the end closest to the passenger compartment and a horizontal peg closest to the engine.
When you release the clip, you can rotate the connector up till the 'business end is clear of the hole in the blower assembly, then slide it to the right (towards the steering wheel). off of the peg, and lift it up into clear sight, attached to the loom.
On inspection it was seen that there was signs of arcing on the exposed connector at the clip end.
looking into the exposed hole in the top of the blower assembly (through the windscreen with a torch) it could be seen that there were two male spade connectors sticking up which the contacts on the plug were 'supposed to mate with' when it was clipped into place, but in practice fail miserably to make a good reliable long term connection. The spade connector at the front, pivot end, (which is the +ve one) is a 3/16" or 4.8mm spade and the rear one (-ve, which goes back to the resistor block) is a 1/4" or 6.3 mm one.
The obvious answer was to make up two wire 'tails' with the appropriate female spade connectors crimped on, put them on the exposed male spades and splice the wires into the feed cables before the plug. Sounds easy doesn't it?
Trouble is that you have to do this from inside the car with no way of seeing what you are doing.
Well I solved the problem by taping a small screw driver vertically to the female connector and wire a with my trusty assistant (our combined ages are 143!) standing on a stool, peering through the windscreen with a torch saying 'left a bit, right a bit, back a bit, now push down', we had both wires firmly connected in about ten minutes
The next stage was to expose a short area of both feed wires on the loom, behind the crappy plug, connect the appropriate tail from the motor to them, solder in place and liberally cover both connections with insulation tape.
I also wrapped the 'business end' of the redundant plug with several layers of pvc tape to prevent any possible shorting out behind the dash.
It was fairly easy then to tuck the old plug behind the main loom and secure it with a cable tie to prevent rattles.
At this point it seemed a good idea to actually test that the fix had work and lo and behold we have a working blower again that functions on all settings.
This still left the exposed elongated oval hole in the top of the blower assembly that had the two new wire coming out of it., anything dropping in there would be likely to cause a short circuit and smoke!
I solved this by taking a large piece of BluTack (about 65mm by 25mm) and moulded it over the hole and around the wires, job done!
All that was left to do was to reinstate the dash top panel and put all of the tools away.
It ain't easy but it can be done with minimal cost.
Jobs a goodun!
That’s the way I like it at zero cost, just a few hours improvise, adapt & overcome work around is my kind of solution.
Congratulations John D and your assistant for an excellent post, it’s difficult being a contortionist with age, I find a dose of Solphodine helps
So you’re aged 141 with a 2 year old to help you?
We have to improvise and adapt to continue motoring on a budget
That’s where forums like these are a lifesaver
I wish you good luck and good health
So you’re aged 141 with a 2 year old to help you?
We have to improvise and adapt to continue motoring on a budget
That’s where forums like these are a lifesaver
I wish you good luck and good health
I might well have got away with another few weeks/months of unreliable use by merely straightening up the buckled contacts in the rearmost connector of the plug and refitting it, but the design is so poor, the contacts, that are supposed to spread and slide either side of the spade connectors, are so flimsy that they just buckle up and end up just sitting on the top edge of the spade, where they inevitably arc when required to pass any reasonable amount of currentJobs a goodun!
That’s the way I like it at zero cost, just a few hours improvise, adapt & overcome work around is my kind of solution.
.The front, +ve connection is not really effected so much as it's proximity to the pivot point of the plug ensures better alignment and positive downward pressure with the spade connector, it's the rear connection, that is much less reliably aligned with the spade with less positive downward pressure, due to it being held down by a springy plastic clip.
I'd put money on the fact that 99% of K12 heater motor failures are just down to bad connections and that there is nothing wrong with the actual motor. I wonder how many owners have shelled out hundreds of pounds to have a new motor fitted unnecessarily ?
I'm resurrecting this thread as my blower stopped working completely a couple of months ago and with the arrival of the cold wet weather I thought that I should get my arse in gear and fix it.
Well as anyone familiar with this problem on the RH drive K12 will know, that to replace the blower motor is a mega difficult job entailing stripping out the whole dash and/or removing the steering column and pedal assembly
This common 'motor failure' (which it actually isn't) is due to the poor design of the plug/socket arrangement on the blower assembly
I realised that I could get at the plug/socket by removing the top cover of the dash (first the good news), however you can only really see it from the outside of the car, through the windscreen!
Having studied it that way I realised that the connector had a clip at the end closest to the passenger compartment and a horizontal peg closest to the engine.
When you release the clip, you can rotate the connector up till the 'business end is clear of the hole in the blower assembly, then slide it to the right (towards the steering wheel). off of the peg, and lift it up into clear sight, attached to the loom.
On inspection it was seen that there was signs of arcing on the exposed connector at the clip end.
looking into the exposed hole in the top of the blower assembly (through the windscreen with a torch) it could be seen that there were two male spade connectors sticking up which the contacts on the plug were 'supposed to mate with' when it was clipped into place, but in practice fail miserably to make a good reliable long term connection. The spade connector at the front, pivot end, (which is the +ve one) is a 3/16" or 4.8mm spade and the rear one (-ve, which goes back to the resistor block) is a 1/4" or 6.3 mm one.
The obvious answer was to make up two wire 'tails' with the appropriate female spade connectors crimped on, put them on the exposed male spades and splice the wires into the feed cables before the plug. Sounds easy doesn't it?
Trouble is that you have to do this from inside the car with no way of seeing what you are doing.
Well I solved the problem by taping a small screw driver vertically to the female connector and wire a with my trusty assistant (our combined ages are 143!) standing on a stool, peering through the windscreen with a torch saying 'left a bit, right a bit, back a bit, now push down', we had both wires firmly connected in about ten minutes
The next stage was to expose a short area of both feed wires on the loom, behind the crappy plug, connect the appropriate tail from the motor to them, solder in place and liberally cover both connections with insulation tape.
I also wrapped the 'business end' of the redundant plug with several layers of pvc tape to prevent any possible shorting out behind the dash.
It was fairly easy then to tuck the old plug behind the main loom and secure it with a cable tie to prevent rattles.
At this point it seemed a good idea to actually test that the fix had work and lo and behold we have a working blower again that functions on all settings.
This still left the exposed elongated oval hole in the top of the blower assembly that had the two new wire coming out of it., anything dropping in there would be likely to cause a short circuit and smoke!
I solved this by taking a large piece of BluTack (about 65mm by 25mm) and moulded it over the hole and around the wires, job done!
All that was left to do was to reinstate the dash top panel and put all of the tools away.
It ain't easy but it can be done with minimal cost.
Thanks to John D for this great post.
Having twice had problems with bad connections at the Resistor my recent problem was as John D indicates at the fan motor connections. Not having ever opened a Dashboard before I was a bit apprehensive but unnecessarily so. The door seal at the windscreen pillars rolls back easily and the pillar trims prise off easily as does the entire top of the dashboard in one piece. Re-assembly is also surprisingly easy.
As regards the motor connections, due to time constraint I was unable to disconnect the hinged connector but got the fan going by jiggling the wires into it. Will have to re-attempt for proper cure as per John D. I am wondering if "tails" could be attached to two wires with straight connectors instead of soldering, but maybe this is not practical ?
Thanks again to John D and hope this helps the apprehensive.
Having twice had problems with bad connections at the Resistor my recent problem was as John D indicates at the fan motor connections. Not having ever opened a Dashboard before I was a bit apprehensive but unnecessarily so. The door seal at the windscreen pillars rolls back easily and the pillar trims prise off easily as does the entire top of the dashboard in one piece. Re-assembly is also surprisingly easy.
As regards the motor connections, due to time constraint I was unable to disconnect the hinged connector but got the fan going by jiggling the wires into it. Will have to re-attempt for proper cure as per John D. I am wondering if "tails" could be attached to two wires with straight connectors instead of soldering, but maybe this is not practical ?
Thanks again to John D and hope this helps the apprehensive.
I'm resurrecting this thread as my blower stopped working completely a couple of months ago and with the arrival of the cold wet weather I thought that I should get my arse in gear and fix it.
Well as anyone familiar with this problem on the RH drive K12 will know, that to replace the blower motor is a mega difficult job entailing stripping out the whole dash and/or removing the steering column and pedal assembly
This common 'motor failure' (which it actually isn't) is due to the poor design of the plug/socket arrangement on the blower assembly
I realised that I could get at the plug/socket by removing the top cover of the dash (first the good news), however you can only really see it from the outside of the car, through the windscreen!
Having studied it that way I realised that the connector had a clip at the end closest to the passenger compartment and a horizontal peg closest to the engine.
When you release the clip, you can rotate the connector up till the 'business end is clear of the hole in the blower assembly, then slide it to the right (towards the steering wheel). off of the peg, and lift it up into clear sight, attached to the loom.
On inspection it was seen that there was signs of arcing on the exposed connector at the clip end.
looking into the exposed hole in the top of the blower assembly (through the windscreen with a torch) it could be seen that there were two male spade connectors sticking up which the contacts on the plug were 'supposed to mate with' when it was clipped into place, but in practice fail miserably to make a good reliable long term connection. The spade connector at the front, pivot end, (which is the +ve one) is a 3/16" or 4.8mm spade and the rear one (-ve, which goes back to the resistor block) is a 1/4" or 6.3 mm one.
The obvious answer was to make up two wire 'tails' with the appropriate female spade connectors crimped on, put them on the exposed male spades and splice the wires into the feed cables before the plug. Sounds easy doesn't it?
Trouble is that you have to do this from inside the car with no way of seeing what you are doing.
Well I solved the problem by taping a small screw driver vertically to the female connector and wire a with my trusty assistant (our combined ages are 143!) standing on a stool, peering through the windscreen with a torch saying 'left a bit, right a bit, back a bit, now push down', we had both wires firmly connected in about ten minutes
The next stage was to expose a short area of both feed wires on the loom, behind the crappy plug, connect the appropriate tail from the motor to them, solder in place and liberally cover both connections with insulation tape.
I also wrapped the 'business end' of the redundant plug with several layers of pvc tape to prevent any possible shorting out behind the dash.
It was fairly easy then to tuck the old plug behind the main loom and secure it with a cable tie to prevent rattles.
At this point it seemed a good idea to actually test that the fix had work and lo and behold we have a working blower again that functions on all settings.
This still left the exposed elongated oval hole in the top of the blower assembly that had the two new wire coming out of it., anything dropping in there would be likely to cause a short circuit and smoke!
I solved this by taking a large piece of BluTack (about 65mm by 25mm) and moulded it over the hole and around the wires, job done!
All that was left to do was to reinstate the dash top panel and put all of the tools away.
It ain't easy but it can be done with minimal cost.
≠=======
Worked a treat for me too, thank you.
I used a small mirror to navigate about , this was perfect if you don't have a helper.
I decided to try some small pin terminals pushed deep into the original plug then the use of cable shrink wrap, to secure each wire to its post, seems fine and I will report back if any problems arise.
Well over 18 months on, mine is still working perfectly
I have this problem on my wife’s car. She’s a senior nurse so needs her car, so I’ve got limited time to fix it.
The thought of her being stuck with no heater fan terrified me, so a quick solution was needed..
I stripped the top of the dash down to get to the typical Renault designed cockup of an electrical connector.
As others have said, if you jiggle the wires a bit the fan starts working.
My first thought was to leave the dash top off so the missus could shove her hand down the front of the dash if the fan stopped.
So... after an ear bashing I came up with plan B.
It needed remote control.. or as most people call it “a piece of string”.
One end tied to the wire, and the other end dangling by the steering wheel. (Think I’ll apply to Renault as a designer).
Top of dash back on.
Job done.
Today I’m going to fix it properly.. stay tuned. ?
The thought of her being stuck with no heater fan terrified me, so a quick solution was needed..
I stripped the top of the dash down to get to the typical Renault designed cockup of an electrical connector.
As others have said, if you jiggle the wires a bit the fan starts working.
My first thought was to leave the dash top off so the missus could shove her hand down the front of the dash if the fan stopped.
So... after an ear bashing I came up with plan B.
It needed remote control.. or as most people call it “a piece of string”.
One end tied to the wire, and the other end dangling by the steering wheel. (Think I’ll apply to Renault as a designer).
Top of dash back on.
Job done.
Today I’m going to fix it properly.. stay tuned. ?
replaced my wifes heater on her rhd micra about 7 years ago at a nissan garage, when the car was worth something.
I had fiddled with the wires for some time, before it eventually gave up working.
Now the new motor is playing up in the same way.
After reading these posts it is now becoming obvious that the spade connectors in the motor are burning and becoming non conductive.
I am now trying a new method to prevent further arching in the hope that it saves the connectors from further damage.
Instead of pulling the wires, I have concluded that putting pressure on the connector would make a better connection.
I achieved this by forcing a piece of expanding foam packing material between the motor connector and the inside of the upper dash surface by reaching up to the motor from underneath the dash, forcing the connector to sit properly.
To minimise further arching between the motor contacts, I have asked the wife to turn the heater motor off before
starting the car.
When the car is started she can build up the speed and resulting current on the motor slowly instead of the full power which is no doubt happening if the switch is left on all the time at the highest speed . This should hopefully prevent or at least minimise any severe arching.
Heres hoping.
I had fiddled with the wires for some time, before it eventually gave up working.
Now the new motor is playing up in the same way.
After reading these posts it is now becoming obvious that the spade connectors in the motor are burning and becoming non conductive.
I am now trying a new method to prevent further arching in the hope that it saves the connectors from further damage.
Instead of pulling the wires, I have concluded that putting pressure on the connector would make a better connection.
I achieved this by forcing a piece of expanding foam packing material between the motor connector and the inside of the upper dash surface by reaching up to the motor from underneath the dash, forcing the connector to sit properly.
To minimise further arching between the motor contacts, I have asked the wife to turn the heater motor off before
starting the car.
When the car is started she can build up the speed and resulting current on the motor slowly instead of the full power which is no doubt happening if the switch is left on all the time at the highest speed . This should hopefully prevent or at least minimise any severe arching.
Heres hoping.
At best a temporary solution........the connectors in the 'plug' are supposed to actually clip over the spade connectors in the motor, not just press on them, something the design fails miserably in achieving.......